4WVP:
reference: The Elastase-PK101 Structure: Mechanism of an Ultrasensitive Activity-based Probe Revealed., Lechtenberg BC, Kasperkiewicz P, Robinson H, Drag M, Riedl SJ, ACS Chem Biol. 2015 Jan 22. PMID: 25581168

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).